Carbureter



H. K. TARKINGTON.

CARBURETER.

' APPLICATION FILED 0CT=18, 1916. 1,398,707. Patented Nov. 29, 1921.

3 SHEETS-SHEET l.

- H. K. TARKINGTON.

CARBURETER APPLICATION FILED OCT. 18, I916.

Patented Nov. 29

3 SHEETS-SHEET 2.

UNITED STATES PATENT OFFICE.

HARRY TARKIN'GTON, OF CHICAGO,

nJLmoIs, iassieivon or ONE-HALF 'ro H(')W'.ARD L. BABCOCK, OF CHICAGO,ILLINOIS.

I cannunn'rnn.

To all whom-it may concern:

Be it known that I, HARRY K. TARKING- TON, a citizen of the UnitedStates, residing at Chicago, in the county of Cook and State ofIllinois, have invented certain new and useful Improvements inCarbureters, of which the following is a specification.

This invention relates to improvements in carbureters of the generaltype employed with internal combustion engines for the 'production ofthe explosivecharge thereof; .and it has as its main and primaryobjectthe provisionof a device of this character, the construction of which issuch as to dispense with the use offioat chambers and theirappurtenancesand to substitute therefor a construction operating under variablepressure. f

The use of float chambers in carbureter construction is attended withmany difi culties. Notable among the same is the frequentflooding of thecarbureter due to the sticking of the float, resulting in fire risk andattendant loss 0 the hydrocarbon fuel, and likewise the abs rptionby thefloat of the liquid fuel destroys its buoyancy and precludes propercontrol of the fuel through the instrumentalities associated with thefloat. These difiiculties are recognized more pronouncedly in themanipulation of automobiles'in which the operation of the carbureters isfrequently impaired 'by theconditions recited.

The present invention therefore seeks to provide a carbureter which isdesigned to overcome the conditions noted, and in which the feed of theliquid fuel is induced and "controlled by the suction of the enginepistons, which suction operates to create a vacuum condition within -the.carbureter.

The feed is therefore proportionate to the 1 speed of and load upon theengine and only somuch of tlieluel is utilized as is actually required.1 1 .The invention further aims to provide a carbureter having simple.and novel means for controlling the flow ofthe fuel proportionately tothe range of operation of the throttle valve, whichcontrol may beeffected both manually and automatically,'whereby to graduate thequantity of the fuel required for varying load conditions and to insureSpecification of Letters Patent. Patented Nov. 29, 1921.

Application filed October-18, i916. Serial'Ro. 126,238. W '1 a properminturein the production of the 4 explosive charge.

Furthermore, the invention also has in view the production of acarbureterhaving minimum.

Witlfthese "general objects in view, and others which'will ap ar as thenature of the improvements is etter understood, the invention consistssubstantially in the novel construction, combination and arrangement ofparts hereinafter fully described,

illustrated in the accompanying drawings,

and finally pointed out in the appended claims. v

ile the forms of the invention herein shown and described are believedto be preferable embodiments thereof,it is to be understood-that thesame merely'depict particular adaptations. The. invention is susceptibleof various changes and modifications, and in the presentation of theseembodiments it is understood that no limitations upon the inventionitself necessarily inhere therein, but the right is reserved to change,modify or vary. the invention within the scope of the claims. Q

.In the. accompanying drawings Figure l is a side elevation of acarbureter' constructed in accordance with the principles of, thepresent invention. I

Fig. 2 is a. similar view at the air intake and gas outlet side at thesame.

Fig. 3 is a vertical transverse sectional view on a medial line of thecarbureter.

I Fig. 4 is a view similar to Fig. 3, illustrating another form of theinvention.

Fig. 5 is atop plan view, partially in section, of the structureillustrated in Figs. 1, 2 and 3.

Fig. 6 is also a fragmentary elevation, s with parts of the needlevalve-controlling mechanism'ina position. of adjustment to which thesame may be moved when starting the motor with which the carburetor isassociated.

' and a similar bottom 12, the top and bottom being held in positionupon the body 10 by screws 13 or their equivalent. The body 10 is)provided with an air intake 14 and an explosive mixture outlet 15. Theoutlet 15 is in the form of a sleeve having a coupling flange 16 topermit the same to be connected to an explosive motor. llithin theoutlet 15 is a throttle valve 17, preferably of the butterfly type, andthe axis of this valve extends to the outside of the outlet 15, at whichpoint it is provided with an operating arm 18. To this arm 18 isconnected the usual actuating devices for manipulating the throttle.

Within the body 10 and at a point adjacentto the lower side of theoutlet 15 is a partition 19,'rising from the central portion of which isa tubular guide 20. At one side of the body 10 and at a point below thepartition 19 a fuel inlet 21 is provided, which inlet is surrounded by ascrew-threaded boss 22, to which a feed pipe leading from the supply ofthe liquid fuel may be connected. It is proposed to rely on variablepressure conditions within the carbureter for feeding the liquid fuel tothe same, as will be explained'more fully hereinafter, and. to preventreturn of that portion of the fuel which remains within the carbureterwhen the operation of the motor has ceased, the feed line at a pointbetween the supply and the 'carburetershouldbe provided with a checkvalve. The application of such a check 'valve will be obvious.

The present invention embodies and operates on the principles of aVenturi tube and it therefore includes a tapered throat for the passageof the air on its way to be mixedwith the liquid fuel. This constructionis attained by means ofa movable air valve 23 which fits the bore of thebody 10 and, is slidably mounted therein. The movable valve 23 is in theform of a cylindrical shell, the bore of which is tapered from. a pointmidway its ends to the ends of the shell, the tapering of the boreextending in opposite directions, asclearly illustrated. in Fig. Thebore of the "valve 23 therefore flares outwardly toward the air intake14 and inwardlytoward the outlet, 15. At the lower end of the movablevalve 23 is arranged a disk 24 having a plurality of openings 25 thereinto afi'ord communication between the bore of the valve and the lowerwearer ceived by the tubular guide 20 and at its lower end is providedwith a plunger or piston 29.

Arranged within the tubular stem 27 and I rising upwardly from thebottom 12 is a 76 tubular guide 30. The guide 30 is obviously astationary element and the stem 27 is adapted to move along said guideas the valve 23 is operated in the manner hereinafter described. At theupper end of the guide 30 is arranged a. stationary air valve 31, saidvalve having a screw-threaded engagement 32 with the guide 30 andthereby being displaceable from said guide. The valve 31 serves thepurpose of a cap for the guide 30 and thereby closes its upper end. Theedges of the valve 31 are beveled to conform to the angle of the upperend of the flared bore of the valve 23, the flared bore, and the bevelededges cooperating to close the space within the throat and thereby cutoff communication between the air intake 14 and the interior of the body10 below the valve 31. The valve 31 is also provided at its lower endwith an annular flange 33 arranged in spaced relation to the bodyportion of the valve and the sides of the latter are also provided withports 34 which communicate with ports 35 formed in the sides of theguide 30. These ports 3t 100 and 35 permit the flow of the liquid fuelfrom the interior of the guide 30 to the interior of the body 10 andas'the fuel emerges through said ports it is brought into contact withtheair passing between the edges 105,

of the valve 31 and the bore of the valve 23, when the latter isunseated.

The stationary valve 31 is also perforated to permit passage of a needlevalve stem 36, the lower end of which is provided with 11 a. needlevalve 37 which cooperates with a valve seat 38 screw-threaded within theguide 30. The stem 36 is connected to a screw 39 fitted within aninwardly ext-ending sleeve 40 carried by the top 11 of the 1 carbureter.This screw 39 has a milled head 41 at the exterior of the carbureter topermit manual adjustment of the needle valve stem 36 and thereby toregulate the relation of the needle valve 37 with respectto its seat 38.To hold the valve in its various 1 positions of adjustment, a springdetent 42 is arranged in juxtaposition to the milled head 41 and exertsits pressure against the serrated edges of said head to prevent rot-aforthe passage of the fuel to dash-pot when such 30 is also provided upwardmovement pinion, it will be seen that the needle valve 37 may be causedto approach or recede from the seat 38. At the same time the rotation ofthe shaft 44 causes the pinion 43 to raise or lower the needle valvestem 36,the screw 39 and the pinion 43 acting in the capacity of a rackand gear. a

v Reference has been made to the plunger or piston 29 which is carriedat the lower end of the stem 27. This" plunger is arranged to workbetween the partition 19 an the bottom 12, and the space between theseparts therefore-constitutes a dash-pot. Within this dash-pot andinterposed between the bottom 12' and the plunger 29 is a coile spring45. This springis of sufiicient strength to maintain the plunger 29 inthe upper end of the dash-pot when the engine is at rest and no suctionis created to separate the valves 23 and 31. The limit of of the plunger29 is such as not to close the port 21 and inasmuch as this portconnects with the feed line leading from the liquid fuel supply it willbe seen that the liquid fuel may pass through the port 21 and into thespace between the parti- P and to provide the space below the plungerthe latter has a port 47 controlledby a suitable check valve 48,- Theurpose' of this valve 48 is to prevent return of the liquid fuel whichhas passed beneath the plunger 29. Communication between the dash-potand the interior of the guide 30 is afforded by one or, more ports 49arranged'at the lower end of said guide. With the fuel. present in thedash-pot the same will flow through he ports 49 to the interior of theguide 30, and on the initial starting of the engine the depression ofthe movable valve 23 will wardly, which in turn forces the liquid fuelinto the guide 30 and upwardly therein to the valve seat 38, which it;needle valve 37 has'been prope ly adjusted in relation thereto. Thebottom '12 has a screw-threaded boss 50 which may be closed by asuitable pet cock, said boss communicatin with theinterior of the guide30 and permitting drainage of the latter and the is desired. The guide Iwith supplementary ports 51 so that when the plunger 29 is forceddownwardly a sufficient distance to pass said .ports, the liquid fuelmay fee directly from the port 21 through the ports 51 and into theguide '30 without passing into the space'beneath the plunger.

It is intended that the needle valve 37. shall move simultaneously withthe throttle a proportionate flow of the be had with regard to the ofthe throttle valve. To

tion 19 and the plunger 29,

' liquid fuel may degree of opening this end the shaft has a connectingarm 52 attached to one pf shaft. This arm =The stud 57 is carried by dto a link 59, the' upper end of which is the stud 57 is likewise themotor. In other words,

force the plunger 29 down-' passes when the.

- valve 17.

of the throttle valve '17 hub on which its 'proj ecting ends.

One end of thisarm 52 is bifurcated as at 53 for receiving the shaft r54 of the throttle valve, and by means of said bifurcation and aclamping screw 5 the arm 52 is held in fixed position on sai 52 is alsoprovided with a slot 56 and working in said slot is a stud 57 which maybe locked at different points in said slot 56 by means of a securing nut'58. i

and articulated provided with a similarly mounted stud 60, said stud 60being received by a slot 61 screw 64 on the projecting end .of the shaft44. .The stud 60, however, hasfree sliding movement in theslot 61, for apurpose to be presently explained, but inasmuch as the arm 62 is clampedupon the shaft 44 and as formed in an arm 62 provided with a bidfurcated end 63 which isheld by a clamping held in fixed relation to theslotted arm 52, it will be apparent thatv as the arm 52v is swung inunison with the movement of the throttle valve 17, the arm 62 willlikewise be moved and through the inion 43 and screw 39 the needle valvewill be simultaneously opening orclosing movement valve.

The link 59 is adjusted to the arm 52 in accordance with the size of themotor and the volume of fuel which it is necessary to feed for thedevelopment of the power of it is obviously of the throttle It is alsoessential that there shall beanadequate supply of the fuel for startingthe engine in its cold condition. There are times also when it is"desired to' speed up the engine more quickly than atothers, as forinstance in speeding der certain conditions. To the present inventioncontemplates a manual adjustment pendently This is accomplished by anactuator cam-65 eccentrically mounted on the said shaft. ,The cam 65 hasan arm 66 to which is connected an operating cable or cylinder motors 37adjusted in relation to its seat 38 in proportion to the degree of anautomobile un-, provide for this,

of the needle valve 37 indeof the opening of the throttle d shaft 44and. independently movable of 1 wire 67 designed to lead to a distantpoint, a

such as the seat of the automobile, and to provide for the properoperation of the cable or wire it is incased in a tube 68 supported fromthe'body of the carbur'eter by a suitable bracket 69. The cam 65' has-ais loosely fitted an eccenthis strap 71 is also protric strap 71 and airin accordance .motor or the load imposed upon the motor.

tion hereinbefore recited.

vided with an arm 72 which receives the threaded end of the stud Mountedon the threaded end of the stud 60 is a spacing washer 73 against whichthe arm '72 is pressed by a nut- H. The eccentric strap 71 is held onthe hub 70 by a clamping plate 75 which is secured to said hub by a '76or its equivalent. When. the arm swung upon the shaft H by the operatingcable or wire 67, as shown in Fig. 6, the cam will actuate the arm 72through the hub and the strap 71 and the eccentric niot'ement of the camwill thereby shift the stud 60in the slot'til. The arm 62 is therebyswung and this movement of the arm rotates the shaft it which, throughits connections with the valve stem 36, causes movement of the needlevalve'37 away from its seat 38 and afiords flow of the necessary amountof the fuel to provide for'thestarting'of the motor in its cold speedingup the motor under the condi- The arm '72 also performs the function ofshifting the stud 60 along the slot 61 and thereby varying the degree ofthrow of the arm 62 when the throttle valve 17 is opened or closed. Thisvarying movement of the arm 62 will result in a varying movement of theneedle valve 37 with a resultant 'arying feed of the fuel inproportionjto the movement of the throttle valve 1?.

Tn Fig. 4i is illustrated a slightly modifi'ed form of the invention.This form is designed to automatically proportion the flow of the fueland the feeding of the with the speed of the T11 this form the body 10of the carbureter is provided with a slot I? through which extends anarm 78 connected to the movable air .valve 23. A link 79 is pivotallyconnected to the arm 78 and also to an arm 80 connected to the shaftett. Hence, as the movable valve 23 is operated, the arm 78. link 79 andarm 80 causea simultaneous rotation of the shaft -14; so that the needlevalve is caused to approach or recede' from its seat to an extentproportionateto the speed of the motor. This is due to the fact that ifthe speed of the motor is decreased or increased the suction of thepistons will be decreased or increasedmnd the movement of the valve 23will vary in accordance with the degree of this suction. The chargetherefore is proportioned tothe speed of the motor and likewise theload. on the motor which, of course, varies the speed of the motor.

It is to be noted that the valve 23, wlien in its normal position ofrest. projects across the air intake 1% substantially one-half the areaof said intake, as seen in Figs. 2, 3 and 4. By reason of thisrestriction of the air intake t e suction 0n the fuel at the conditionor for wearer ports 34 and 35 will be the greatest when the valves 23and 31 are in contact with each other, or are in closed position, asshown in Fig. 3, and as they separate under the suction of the pistons,the effective area- 7( of the intake will become enlarged gradually butproportionately to the extent of opening of the valve 23 and alsoproportionatelyto the speed of the motor. This insures flow of the fuelat; the ports 3% and 35 when, starting the engine. The operation of theherein described car,- b'ureter is as follows: The fuel passes throughthe port- 21, through the valve controlled port 47 into the dash-pot andenters the. guide 30. The engine being at rest, the fuel willnotdischarge to the interior of the body 10, but will remain within theguide 30. The needle valve 37 should be adjusted, of course, properlywith relation to its seat. ()n the starting of the engine, a suctionwill be created within the carbureter. establishing a vacuum action anddrawing the fuel upwardly in the guide 30. This vacuum action. however,will also draw themovable valve 23 downwardly and with its descent theplunger 29 will be forced downwardly against the tension .of the spring45. This forcibly ejects a quantity of the fuel from the guide 30through the ports 34 and 35, and as the movementof the valve 23 hasprovided a space between the same and the stationary valve 31, air alsowill be drawn through the intake 1-1 and into the interior of the body10\to be mixed 1- withthe fuel discharged from the guide 30.

The intake 14 should be connected to a jacket about the exhaust of theengine so that the air entering through the intake '14- may bepreheated. The reasons for this are 1 5 obviously to promote thevaporization of the fuel. As the engine'continues to operate,

the suction of its pistons will maintainthe flow of the. fuel, and thisflow will be in w direct proportion to the extent that the 11 valve 37is opened in relation to the degree of movement of the throttle valve17. It will be understood that as the throttle valve 17' is operated toa greater or less extent, the needle valve 3? will also be'operatedthrouglr the arm 52. the link. 59, the arm 62, theshaftat and theconnections of the latter with the needle valve stem 36. Should it bedesired to speed up the engine to a greater extent the operation of the.throttlel'T, as under normal conditions, the actuator cam 65'ismanipulated in the manner hereinbefore described to increase the flow ofthe fuel as also described.

When the engine is stopped, it will be understood that the fuel remainsin the guide 30, being held therein by the check valve in the feed line,and immediately upon the engine being than is rendered possible by ,120

again started, a supply of thetfuel isavailable at the ports 34 and 35to provide for immediate discharge of the fuel at this point.

The space below the valves 23 and 31 and above the partition 19constitutes the mixing chamber of the carbureter. WVith the valve 23seated against the valve 31, the mixing chamber is effectually sealedagainst communication with the air intake 14. Should, therefore,back-firing occur, the pressure incident thereto will seat the valve 23against valve 31 and prevent passage of the gases therethrough, so thatfire risk is reduced to aminimum.

Having thus described the invention, what is claimed as new and desiredto be secured by Letters Patent is:

1. In a carbureter, the combination of a casing affording an air inletpassage and a suction passage, a chamber for liquid fuel and having acheck controlled fuel inlet, a valve for regulating passage of liquidfuel between the chamber and suction passage, a piston operable in saidchamber to increase the velocity of discharge through said valveindependently of the valve adjustment, and means responsive todifferences of'pressure between the inlet passage and suction passagefor operating said piston.

2. In a carbureter, the combination of a casing affording an air inletpassage and a suction passage, a chamber for liquid fuel and having afuel inlet, a valve for regulating passage of liquid fuel from saidchamber to the suction passage, means operable in said chamber toincrease the velocity of discharge through said valve independently ofthe valve adjustment, and means operable through flow of air from theinlet passage to'the suction passage for operating said means. v 4

3. In a carbureter the, combination, of a casing affording an inletpassage and a suc-' tion passage, a control member movable underdifference of pressure between said passages for controllingcommunication therebetween, a chamber for liquid fuel, a piston operabletherein, a connection between said piston and said control memberwhereby the movement of the latter is opposed by liquid in the chamber,means affording a valve port allowing communication between said chamberand the suction passage, and

a valve for controlling the effective area of said port; the movement ofsaid control member under suction being effective to force liquid fromthe chamber through the valve port.

4. In a carbureter, the combination of a casing affording an inletpassage and a suction passage, a chamber for liquid fuel, a

tube extending into said chamber and-having communication therewith andWith the suction passage, a valve in said tube for controlling passageof fuel from the chamber to the suction passage, a sleeve slidablyguided on the tube, a piston operable by the sleeve in the chamber toforce fuel therefrom through the tube, and a member controllingcommunication between the inlet and suction passages cooperating withsaid sleeve to move the iston.--

HARE K. TARKINGTON. \Vitnesses:

MILTON T. MILLER, VILLIAM N. CROMWELL.

